Psychological Inflexibility and Its Associations with Chronotype and Sleep Quality in Spanish Adults

The primary objective of this study was to analyze self-reported sleep perception in relation to psychological inflexibility traits in adults.A total of 705 adults (65.2% women) participated, with a mean age of 27.21 years (standard deviation =10.67).The instruments used were the Pittsburgh Sleep Quality Index, the Composite Scale of Morningness, and the Acceptance and Action Questionnaire.Results showed that participants with high psychological inflexibility had a significantly greater risk of reporting poor sleep quality [odds ratio (OR) =2.632] and identifying with an evening chronotype (OR =2.825) than those with lower inflexibility scores.Higher inflexibility scores were positively associated with sleep disturbances, daily dysfunction due to poor sleep quality, use of sleep medication, and other sleep-related issues.Targeting behaviors associated with psychological inflexibility could help improve sleep-related outcomes.